Perpetual calendar.



No. 651,940. 4 Patented .lune |95, |300.

E. G. TASSO.

PERPETUAL CALENDAR.

(Application led Aug. 17, 18993/ (No Model.)

RPRl'SIEPT 4 JAN. APR JULY oec. A ocT. uuLY :u E' a.

fg `.4- Y 0 l 9 lo c, 7 's |5 -[2- l2 20 2| I7 18 26 27 23 -24- -S a2 -28- 28 .2.9 5- 3l8 4o g c 4a -44- 4s 4a j gg,

if' 2a 5% c 65 66 s s 7l -72- 73 74- 76 77 73 80. 8?. 83 Y 84- 85 88- 88 90 9|V a3 94 5 96 9 :gg loo w L@ 6.300?z 1700 40 Z' fyi w/TNESSES /N VEA/70H Email, GTasso 77'0HNEYS TH: Nonms PETERS co., mamumajwnmumn. u. c.

UNITED' STATES PATENT FFICF..

EMIN e. TAssO, or CAIRO, EGYPT.

PERPETUAL CALENDAR.

sPEoIFIeAtrroN forming part or Lettersratent No. 651,940, dated .nine 19, 1966.

Application filed August 17, 1899. Serial No. 727,610. (No model.)

To all whom t may concern:

Be it known that I, EMIN G. TASSO, a subject of the Turkish Government, residing at Cairo, Egypt, have invented an Improved Perpetual Calendar or Almanac, (registered in the Mixed Tribunal, Cairo, No. 73, bearing date March 27, 1899,) of which the following is a full speciiication. i

My invention, is an improvement in that class of perpetual calendars which are constructed in the form of a cylinder or a polygonal tube. The construction of the same and its novel features are hereinafter described.

In the accompanying drawings, Figure'l is a perspective View of my calendar complete. Fig. 2 isa perspective view of the cylindrical body of the same. Fi g. 3 is a perspective View of the rotatable part or cylinder` inscribed with the names of the months and the numbers indicating the days of a month arranged in columns. Fig. 4. is a perspective View of the other.

rotatable part or cylinder inscribed with the numbers of the years arranged in columns. Fig. 5 is a cross-section on line 5 5 of Fig. 1. Fig. 6 is a diagrammatic planview showing the entire exterior portion of the calendar laid out in the fiat.

The calendar is composed of the following parts: a cylindrical body A, having an enlarged circumferential portion or, and two hollow polygonal tubes B and C. These tubes may, however, be made cylindrical exteriorly, the polygonal form being used merely as preferable for inscribing and reading of numbers thereon. The parts B and C rotate on A, but lit closely enough to have such friction as en- -ables them to retain any position to which the following principle: It is found by calculation that every` such century-year be gins two days earlier in the week than did the preceding century-year, unless such preceding century-yea'r be a leap-year, in which case the century-year following such leapyear begins but one day earlier in the week. Thus the leap-year 1600 began on Saturday. 1700, the next century-year following the leapyear 1600, began one day earlier in the week than did 1600, or on Friday, while` 1800, not following a leap-year century, began two days earlier in the week, or on Wednesday. 1900 in like manner began two days earlier, or on Monday, and 2000 will begin on Saturday; but 2100, following a leap-year century, will begin one day earlier in the Week,or on Friday.

From the above it is seen that the initialday of both leap-years 1600 and 2000 is Saturday and that 1700 and 2100 began on Friday, from which it may be readily deduced that,

according to the Gregorian calendar, every Inasmuch as the present method of counting leap-years is not strictly accurate, it has been proposed to consider the year 3200 and multiples thereof not leap-years, but common years, in order to correct this inaccuracy.

This necessitates a new system of columns in the table, containing the years 3200, 3300, 65o., but constructed on the same principle as above. While the succeeding centuries,'as

above stated, begin two days earlier in the week than their predecessors, the years themselves begin one day later--that is to say, every succeeding year begins one day later in the week than did its predecessor, unless such predecessor be `a leap-year, in which case it begins two days later. Thus the year 1859 began on Saturday, 1860 on Sunday, and 1861 on Tuesday. Hence it will be seen that a table may be readily prepared embodying this principle. outer tube or cylinder C, which is to be used, in connection with the century-years on the IOO Such a table is found on the lower inner cylinder, A, above described, to designate any reqilied year, the iirst two gures day, asY stated, Vand continued through Januf ary and February just as if it had been a common year, it did not so contine after February metal 8 on cylinder Cie repeatedinthe ad-- 29; but, owing tothe interposition of the l tra day, (February 29,) the rst dayof March, es' well es everyday thereafter, was crowded back 'one dayfarther from January lthan it would otherwise have been, and the year was finished lip' as if it had lbegun on Saturday iristead 'of on Friday. For this reason the nil'- jaeent coliinin, and the first one is designated byplaeing it between dashes-,ias shown. The

saine repetition is made for all the leap-years,

as shown on cylinder C. The iirst of these repeated numerals lis, iisedin adjusting the ealen'danas hereinafter described, for the first two months of any leaplyear, or before Febriiar-'yr29, Vwhile the second numeral in the ad'- jaeent coluinn is to be used after February 29.

.'Themupp'er or smaller rotatable tube o`r eyl-V inder B 'carries the inenthenuinerals l to 31,1 arranged in seven eeiumns corresponding to the seven? days ot the week, said arrangement being so well known as to req'u'ir'ev no description; In the saine column with the niier'al 1 of this series and below it, asv

shown in Fig. e, the abbreviation Jani is pinned. 1t will then renew es e neeeteeny` consequence that when the collar or cylinder `Bis: s'o djiisted with respect to the tlxbe C thetJent stende ever the required yearl 'the four items involved in thedate (weekday, month, month-numeral, and year'ywill be in register. Thus in Fig. 6, which shows the parts A and C adjusted for the nineteenthfcentiiiy, there ina'y be read from the sixth eelninn Wednesday, Jen. 1, 180o or r wednesday, Jen. 1,1806. Frein this denne nign'reit is Seen that Jann-ery 31 of these years rene 'on Friday, and itfenewe tnetFehf rndriyi faire en satnrdey. Hence te' eetthe calendar fer Febpnhy the eener B met he; te expeeeieepeyeerethrough epeninge', the turned forward three spaces until the nu- 2 1 thereon registers with f 'Satu'-i day onfthe fixed cylinder A; but the new; l ni'oiith Feb iniist also register with the rel 'qnire'd year- 'on V'tiibe C, as Jan. did before; To this end the naine"rFeb. nust be placed en eenen B three spaces te thei-eft'of Jahr; Since February infco'rnnion years contains eX'- vabtly folir weeks, the ni'onth of March begins l en the` sente dey of -the week es dees nennt ary. Hence the calendar needs no re'adjnst`- r'rfnei'tgil passing `from February to March in ehehv years Abi1ifsin'ee March contains thirty# one days, or three days more than four full weeks,y in setting the calendar for April it will be necessary to turn the collar B forward three spaces,'as explained above, and to place Apr.7 on collar B three spaces to the left of y Since April has but thirty days, May will be placed but two spaces to the left of Ap1'., and the entire set of inonthsnarnes will when completed be of the year on tube 0.', In case of leap-,years the given month, it January or Febrlary, ,mit-register with the Anu'iietals tbe C located between the dashes; bijt if any other month than January or Febrary it Vinst be settol register with the duplicates of these nnnterele in the eoinnm te the right thereof. Thus Figi. 6 shows the calendar set for February5f1809, and also for March, 1809; It is likewise set for Febrliary, Y1804; bijt it is not set for'March, 1804,. To set itV for the latter inonth, the collar C mnst be turned one space tieI the right er until fMan registers with 4e in the fith col-umn'.

Y Itis ths' seenthateve'ry yearendin'g in 4 8 12 16, dto., is a leap-year, no matter in what century it occiirs, and Stich nme'r'als ete always repeated in adjacent columns, ee Seen in Fig; 6, aiidin usingthe calendar `it soon becomes a inatter requiring nojre'asoning tense the dupiieeted yeeenurnereie in the Aman ner above described.Y A diiiclty arises, however, in the case of yearse'ndingv in 00, which are sometimes leap-'years and Aschietines common years. In order to obvi'ate'this diihculty, I have placed on the inner eylinder Aand between dashes a Zero (O) so positioned with relation to the column of 4`century leap-years below that ywhen the tnhelo is se turned as to expose this coliiniiV throngh the lower opening c this extra 0 will show through'th'e upper opening or notch ef at the top of tube C in front of the Zeroecoliinin 6 thereon, and thiis there will be sn'pplied the duplicated year-number, which is to be sed precisely as the dn'plicated leap=year niinbers when both are found on tube C, as above de4 scribed; 1 When this tnbe is not turned so as eXtra '0 on 'cylinder A` is Vhidden behind tubG. Thns, as shown in Fig. 1, the leap= year colinn on cylinder is eX'posedbn this cylinder, while in Fig'. e the leap-year eelninn is represented as not exposed and the-"0 on cylinder A is likewise hidden.'V It is 'tls' seen that 'the 'user may know Withoit'calcla= tien whether any year ending vin l0o in e l'anreai: and Whether or net heist@ shift the collar B between' Febz and n Mar ,f The following is a pi'abtical illustration" of the men-nennt 'neing' the amendant 'suppose the date et 'a persoirs birth t be Aug'nst 19,

IIO

651,946 s Y e 1877. We turn the longer cylinder C on the body A until the centurial number 1800 appears in the slot c. (See Fig. 4.) Then the number 77 is sought, and in this instance it happens to be in the column above 1800 'on cylinder C. The shorter cylinder B is then adjusted to bring the abbreviation Aug directly over orin Vertical' alinement with t-he column on C in which 77 appears. Then we follow around B to the left until we find the number 19, which is directly over and in alinement with the abbreviation Sum on the portion a of body part A. Hence the 19th day of August, 1877, fell on a Sunday. The several marks 19, Sun., 77, and 1800 are indicated by horizontal shade-lines.

The following is another example: Suppose the date given be January 27, 1841. The cylinder C is adjusted, as before, so that 1800 may be read in its slot c. Then adjust cylinder B so that the sign Jau will be in line with the column on C in which 41 appears. Then follow around on B to the left, and 27 will be found over Wed., which is the day sought.

The calendar, as shown, is constructed on the supposition that the Gregorian system has been in operation since the beginning of the Christian era, which of course is not true; but old-style dates may be readily found from the Gregorian dates furnished by the calendar.

1. As an improved article of manufacture, the tubular calendarhereinbefo're described, the saine comprising the inner cylinder, A, having a raised circumferential portion bearing the names of days of the week, and on its lower portion century leap and common years in columns, a tube C, which is applied to and rotates on the cylinder below such circumferential portion, and inscribed with numerals of years arranged in columns, and the shorter tube B, which is applied to and rotates upon the upper part of such cylinder,

and bears the names of months and numerals of days of the months, in columns, the said raised portion of the cylinder forming a stop which the inner ends of the rotatable tubes abut, as shown and described.

2. As an improved article of manufacture,

the tubular calendar hereinbefore described,-

the same comprising the inner cylinder A having a raised circumferential portion bearing' the names of days of the week, and on its lower portion century leap and common years use of the century leap-year column, substan;y

tially as shown and described.

3. The combination with the inner tube A, carrying the names of days of the week arranged serially, and adjacently a symbol 0, and its lower portion having the centuryeyears arranged in seven columns, common and leap years being separated, the outer and lower rotatable tube C, having notches at top and bottom which are spaced apart laterally by the width of a column, and inscribed with seven columns of numerals indicating years, and the upper rotatable tube B, having names of the months and columns of numerals indicating days of the months, the arrangement being such that when the aforesaid symbol 0 is visible through the upper notch of tube C, the century leap-years appearrthrough the lower notch of the same, as

shown and described.

EMIN G. TASSO. Witnesses:

PERcY D. LANGLEY, GEORGES B. ABDELMEssIH. 

